<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <title>Title</title>
</head>
<body>

</body>
<script>
  class Student{
    constructor(name,age) {
      this.name = name
      this.age = age
    }
    say(){
      // 默认use strict
      console.log(this)
    }
  }

  let s1 = new Student('xqz',12)
  s1.say()
  let say = s1.say
  say()
</script>
</html>
